<<

Tutor Tool by Andrey Michel Classification of Vertebrae

Superior view of cervical . Superior view of thoracic vertebra. Superior view of vertebra.

Although the presacral vertebrae share lack transverse are larger than many characteristics, some structures may foramina, and have superior and inferior thoracic vertebrae and lack the derived features only be found on certain types of vertebrae. costal facets for the attachment of . of cervical and lumbar vertebrae. They have no Thus, one may categorize a given cervical, They also have transverse costal facets transverse foramina, transverse costal facets or thoracic or lumbar vertebra by the presence or which articulate with the tubercle of the superior/inferior costal facets. When viewing absence of certain features. For example, the presence of transverse foramina on the . It may be helpful to know that thoracic most lumbar vertebrae from the posterior side, vertebra above indicates it is a are larger than cervical vertebrae, they resemble the of a moose. When vertebra, as only cervical vertebrae possess and many of them look like the head of a using the “ or moose” method, be transverse foramina for the passage of the giraffe when viewed from the posterior cautious, because a thoracic vertebra that is the vertebral arteries and veins. aspect. last of its group will look somewhat more like a lumbar vertebra (moose), and a lumbar

vertebra that is the first in its group will look somewhat more like a thoracic vertebra (giraffe) Special Cervical Vertebrae Dens (odontoid )

Superior Articular Superior Articular Facet Facet

Vertebral body Transverse (hidden) Spinous Process Transverse foramen

Superior view of Superior view of

Like all cervical vertebrae, the atlas (C1) As it is a cervical vertebra, the axis (C2) possesses transverse foramina. However, the atlas possesses transverse foramina. However, unlike may be identified by its large superior articular any other vertebra, it has a post-like structure facets, which articulate with the occipital called the dens which articulates with the atlas to to form the atlanto-occipital , permitting form the atlanto-axial joint, which allows for flexion and extension (nodding). Named for the rotation of the head. Note that the vertebral body greek god Atlas who was believed to carry the and spinous process are present. It is easy to world on his , the atlas supports the remember that these features will be present if weight of the . One may also note the absence one knows that the pre-sacral vertebrae increase of a vertebral body and spinous process, which is in size as they go down the . unique to the atlas.